code: def test_to_simple_rdd(spark_context):
      features = np.ones((5, 10))
      labels = np.ones((5,))
      rdd = rdd_utils.to_simple_rdd(spark_context, features, labels)
  
      assert rdd.count() == 5
      first = rdd.first()
      assert first[0].shape == (10,)
      assert first[1] == 1.0
  
file_path: elephas/tests/utils/test_rdd_utils.py
imports: import numpy
  from elephas.utils import rdd_utils
label_desc: Use image node_id 1 for calling a global function with example usage: test_to_simple_rdd(spark_context) without return types